1. Field of the Invention
The present invention relates to an electronic apparatus, a method of correcting detection data, and a sensor unit that use correction information for computing the corrected value of detection data acquired with a sensing device.
2. Description of the Related Art
FIG. 1 is a diagram illustrating a hardware configuration of a conventional electronic apparatus 1. The electronic apparatus 1, which includes a microcomputer 70, has a sensor unit 60 as its component. The sensor unit 60 has a nonvolatile memory 63 containing correction information for computing the corrected value of detection data acquired with a sensing device 61. The microcomputer 70 is a computing device that computes the corrected value of the detection data acquired with the sensing device 61 using the correction information read from the nonvolatile memory 63.
The correction information is predetermined on a sensing device basis because of variations in detection data among sensing devices. Before the sensor unit 60 is shipped as a component of the electronic apparatus 1, the correction information is written to the nonvolatile memory 63 with the data writer of a manufacturer of the sensor unit 60 or the like. Thereafter, the sensor unit 60, shipped as a component of the electronic apparatus 1, and the microcomputer 70 are assembled as components of the electronic apparatus 1 in the manufacturing process of the electronic apparatus 1.
FIG. 2 is a flowchart of a conventional correcting operation program executed by a central processing unit (CPU) 74 of the microcomputer 70. In step S11, the CPU 74 of the microcomputer 70 communicates with the sensor unit 60 to read data contained in the nonvolatile memory 63 included in the sensor unit 60 and load the read data into a RAM 72. Then, in step S13, the CPU 74 of the microcomputer 70 obtains the correction information in accordance with the memory map of the nonvolatile memory 63 provided in advance from the manufacturer of the sensor unit 60. In step S15, by performing an operation for correcting detection data acquired from the sensor unit 60 using the obtained correction information based on a prescribed correction operational expression, the CPU 74 of the microcomputer 70 calculates the corrected value of the detection data (corrected sensor value).
For example, there are Japanese Laid-Open Patent Application No. 6-160100 and Japanese Laid-Open Patent Application No. 62-218813 as prior art documents related to correcting operations similar to the one described above.